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1.
As the field of ecological risk assessment (ERA) broadens, scientists from various disciplines are called upon to become assessors at hazardous waste sites. Although a United States Environmental Protection Agency (USEPA) Framework for ERAs exists, the guidance is unlike the detailed USEPA guidance available for human risk assessments. Currently, the quality of an ERA is dependent upon the assessor's scientific acumen, professional experience, and recognized reference documents. This annotated reference compilation encompasses published documents which have provided useful and important information for qualitative and quantitative ERAs.  相似文献   

2.
Policy protection goals are set up in most countries to minimise harm to the environment, humans and animals caused by human activities. Decisions on whether to approve new agricultural products, like pesticides or genetically modified (GM) crops, take into account these policy protection goals. To support decision-making, applications for approval of commercial uses of GM crops usually comprise an environmental risk assessment (ERA). These risk assessments are analytical tools, based on science, that follow a conceptual model that includes a problem formulation step where policy protection goals are considered. However, in most countries, risk assessors face major problems in that policy protection goals set in the legislation are stated in very broad terms and are too ambiguous to be directly applicable in ERAs. This means that risk assessors often have to interpret policy protection goals without clear guidance on what effects would be considered harmful. In this paper we propose a practical approach that may help risk assessors to translate policy protection goals into unambiguous (i.e., operational) protection goals and to establish relevant assessment endpoints and risk hypotheses that can be used in ERAs. Examples are provided to show how this approach can be applied to two areas of environmental concern relevant to the ERAs of GM crops.  相似文献   

3.
Traditionally, ecological risk assessments (ERAs) have emphasized risks to individual organisms or populations of species. Although habitats may be a potential target for chemical stressors, and are considered in the framework for ERAs, the actual use of habitat evaluation methods in this process is limited. Habitats obviously represent an important entity to protect since damaged aquatic and wildlife habitats may be totally irretrievable over a human life span compared to deleterious biochemical and physiological changes which may be reversible within the life cycle of an organism, if exposure is terminated. Habitat methods have been largely used as management tools to evaluate impacts of planned water and land development projects. Habitat evaluation methods represent a structured, systematic and logical approach to determine changes to habitats because they consider important life requisites and environmental variables limiting to species. Their use in the ERA process will provide a means to differentiate habitat changes resulting from physical, chemical and/or biological factors or a combination of such factors. In addition, minimal and optimum habitat suitability can be determined for different habitat variables under different chemical exposure scenarios. The objectives of this paper are to review several available habitat evaluation methods and discuss their use in risk assessment. Particular emphasis is given to USFWS's Habitat Evaluation Procedures (HEPs) and the Instream Flow Incremental Method (IFIM).  相似文献   

4.
Ecological risk assessments (ERAs) have largely ignored exposure to wildlife via inhalation on the assumption that it is negligible compared to the ingestion route of exposure. The assessment of inhalation risk also has been limited due to a paucity of relevant ecotoxicity data. This article presents toxicity reference values (TRVs) for small mammals based on chronic or subchronic exposure studies for a range of organic and trace metal contaminants and ecologically relevant inhalation endpoints. Potential risk to small mammals due to ingestion and inhalation exposure were compared in two hypothetical air emission scenarios for a point source (incinerator) and non-point source emissions (vehicular emissions). Using two screening-level ERAs, we conclude that it may now be time to reconsider inhalation risk to wildlife in the case of atmospheric emissions of some metals and volatile organic compounds (VOCs). In the case of birds, the toxicological database remains too small to assess risks via this pathway. However, for mammals, we suggest that inhalation exposures to contaminants such as cadmium, benzene, and other VOCs could be important.  相似文献   

5.
Risk-based methods promise improved decision-making for managing of contaminants, such as salinity, sediments, nutrients, and toxicants, that can adversely affect the ecological condition of aquatic ecosystems. Two aspects of ecological risk assessment (ERA) and management—stakeholder involvement and more quantitative approaches to risk analysis—are particularly challenging. Stakeholder involvement is crucial both in the risk assessment process and the development, acceptance, and implementation of a risk management plan. Additionally, a number of quantitative approaches (particularly Bayesian approaches and multi-criteria decision-making) have been identified as having the potential to include expert-based inputs into risk-based decision-making. These offer promise for better inclusion of stakeholder knowledge and preferences into the decision-making process, and for improving the links between stakeholder inputs and potential risks to the ecological condition of the system. A major challenge for ecologists and natural resource managers is to make the ERA process more quantitative. Most ERAs conducted to date have been qualitative assessments that suffer from a number of deficiencies, the most serious being the lack of transparency and a reliance on subjective judgments. This article argues that the most productive way forward may be to use Bayesian methods to couple existing process-based models, empirical relationships based on good data, and expert opinion, to make the analysis of ecological risks more robust, consistent, and repeatable.  相似文献   

6.
7.
In the past, ecological risk assessments (ERAs) have generally overlooked the soil microbial community when evaluating the impacts of contaminants in soil. However, the soil microbial community, which includes bacteria and fungi, performs functions necessary for overall ecosystem health, including nitrogen fixation, nutrient cycling, and even degradation of contaminants. The incorporation of the soil microbial community into ERA requires the compilation of adequate toxicity data to complete the hazard assessment phase of the risk assessment. A variety of soil microbial toxicity tests exist that provide rapid and inexpensive results. Surveys of the microbial community at a contaminated site may also provide insight as to their functioning in the presence of contaminants. This paper explores the use of toxicity tests and surveys to evaluate chemical toxicity to microbes. However, many questions related to the best methodological approach to an ERA of the soil microbial community have yet to be answered.  相似文献   

8.
Ecological risk assessment (ERA) methodologies must be continually improved so that resource managers, activity proponents, and stakeholders can better manage the environmental impacts of human activities. One of the largest challenges facing ERA methodologies and approaches is to develop the ability to encompass cumulative and far-field effects of human activities. It is argued here that the ERAs of industrial aquaculture activities have been an example of where ERA practitioners and researchers have responded to the challenge of managing the cumulative risks of a new and rapidly growing industry by developing innovative ERA approaches that can be applied elsewhere.  相似文献   

9.
中国外来植物入侵风险评估研究   总被引:1,自引:0,他引:1  
李惠茹  严靖  杜诚  闫小玲 《生态学报》2022,42(16):6451-6463
对外来植物开展入侵风险评估是防止外来植物入侵最经济有效的措施,能够极大的节约外来种管理的经济和时间成本。研究简述了国内外入侵风险评估系统,从外来物种基础信息缺乏、外来植物的适生区分析不完善、风险评估体系构建不客观、对新近外来种的关注度不够4个方面阐述了我国外来植物风险评估存在的主要问题。并针对存在的问题提出了以下建议:(1)构建外来植物基础信息数据库是风险评估的基础,加强外来植物本底资料的调查与考证,并将外来植物表型数据的积累和分析纳入数据库,使得风险评估有据可依。(2)运用生态位模型进行生态风险分析是风险评估的重点,并将人类活动指标纳入预测模型,揭示人类活动对入侵植物分布格局的影响。(3)建立科学的风险评估系统是核心,包括通过选择风险指标和设置权重来提高评估系统的科学性、构建特定区域或特定生态类型的风险评估体系、根据评估对象的生物学与生态学特征建立符合实际要求的评估标准,实行差别化的风险评估等。(4)加强新近外来植物的管理是关键,应定期野外监测新近外来种的种群动态,定期审查风险评估结果,对高风险的新近外来种进行预警研究将为中国外来植物风险评估体系构建提供重要参考,为入侵植物防控措施的制定提供理论依据。  相似文献   

10.
Problem formulation is the first step in environmental risk assessment (ERA) where policy goals, scope, assessment endpoints, and methodology are distilled to an explicitly stated problem and approach for analysis. The consistency and utility of ERAs for genetically modified (GM) plants can be improved through rigorous problem formulation (PF), producing an analysis plan that describes relevant exposure scenarios and the potential consequences of these scenarios. A properly executed PF assures the relevance of ERA outcomes for decision-making. Adopting a harmonized approach to problem formulation should bring about greater uniformity in the ERA process for GM plants among regulatory regimes globally. This paper is the product of an international expert group convened by the International Life Sciences Institute (ILSI) Research Foundation.  相似文献   

11.
Ecological indicators can be defined as relatively simple measurements that relay scientific information about complex ecosystems. Such indicators are used to characterize risk in ecological risk assessment (ERA) and to mark progress toward resource management goals. In late 1997, scientists from the U.S. Environmental Protection Agency and from the Chemical Manufacturers Association (CMA) held a workshop to explore opportunities for collaborative research and scientific exchange on the development and application of ecological indicators. Several scientific challenges were identified as they relate to problem formulation, exposure and effects assessment, and risk characterization. Chief among these were a better understanding of multiple stressors (both chemical and non-chemical), characterization of reference sites and natural variability, extrapolation of measures to ecologically relevant scales, development of comprehensive, ecosystem-based models that incorporate multiple stressors and receptors, and a consistent system for evaluating ecological indicators.  相似文献   

12.
Ecological risk assessment (ERA) is a process that evaluates the potential for adverse ecological effects occurring as a result of exposure to contaminants or other stressors. ERA begins with hazard identification/problem formulation, progresses to effects and exposure assessment, and finishes with risk characterization (an estimate of the incidence and severity of any adverse effects likely to occur). Risk management initially sets the boundaries of the ERA and then uses its results for decision-making. Key information required for an ERA includes: the emissions, pathways and rates of movement of contaminants in the environment; and, information on the relationship between contaminant concentrations and the incidence and (or) severity of adverse effects. Because of specific properties and characteristics of metals in general and of certain metals in particular, a generalized ERA process applicable to organic substances is inappropriate for metals. First, metals are naturally occurring and can arise, sometimes in very high concentrations, from non-anthropogenic sources; organisms can and do adapt to a wide range of metal concentrations. Second, certain metals (e.g., copper, zinc) are essential for biotic health, which means there is an effect threshold for both deficiency and excess, and that standard body burden indices such as bioaccumulation factors (BCFs) can be misleading. Third, metals can occur in the environment in a variety of forms that are more or less available to biota but adverse biological effects can only occur if metals are or may become bioavailable. Fourth, whereas the bioavailability and hence the possibility of toxicity of persistent organic substances are mainly dependent on their intrinsic properties (i.e., lipophilicity), those of metals are generally controlled by external environmental conditions. Examples include pH and ligands, which affect the metal speciation and coexisting cations (e.g., H+, Ca2+) which compete with the metal ions. ERAs involving metals must include the above four major considerations; other considerations vary depending on whether the ERA is for a site, a region, or is global in scope.  相似文献   

13.
Until recently, parameters from microorganisms were generally not included in risk assessment at a comparable level to animals and plants. However, the major part of global biomass, biodiversity, and ecosystem processes is present in the microbial world and microbiological techniques applicable to risk assessment are becoming available. Two microbial indicators are described based on the usage of multiwell plates with different substrates and a redox indicator for monitoring mineralisation. With both techniques autochthonous microbial communities are analysed. Producing functional fingerprints of the microbial community gives insights into the composition of different functions. This is equivalent to observations of ecological abundance and species composition. When lack of reference sites or reference data renders risk assessment difficult, measurement of the pollution-induced community tolerance (PICT) can provide useful information.  相似文献   

14.
宋昌素  欧阳志云 《生态学报》2020,40(10):3207-3217
开展生态效益评估,对于推动生态效益纳入经济社会评价体系、推进生态文明建设具有重要意义。生态效益是指自然界的生态系统对人类的生产、生活条件和环境条件产生的有益影响和有利效果。GEP(Gross Ecosystem Product)是生态系统生产总值,指一定区域在一定时间内,生态系统为人类提供最终产品与服务的经济价值总和,是一定区域生态系统为人类福祉贡献的总货币价值,可以反映一个地区的生态效益。本研究提出面向生态效益评估的GEP核算框架,建立核算指标体系和技术方法,基于遥感数据和统计数据以青海省为例开展面向生态效益评估的GEP核算研究,并对相关利益者进行分析。研究结果表明,2015年青海省生态系统生产总值GEP为464.16亿元,对生态资产产生的生态效益进行相关利益者分析,80%以上生态效益的受益者是青海省以外的区域。以可比价计算,自2000年以来青海省GEP增加32.6%。根据现有的数据体系和方法核算的GEP是有现实意义的,可以作为生态效益评估的指标,可以作为GDP的重要补充对政策效益和生态保护成效开展评估,还可以作为市场化、多元化生态补偿机制建立和"绿水青山"向"金山银山"转化的依据和...  相似文献   

15.
基于生态系统服务的生态风险评价研究进展   总被引:5,自引:0,他引:5  
康鹏  陈卫平  王美娥 《生态学报》2016,36(5):1192-1203
生态风险评价对科学管理与保护生态系统具有重要的意义,为弥补传统生态风险评价方法的不足和提高风险管理的效率,将生态系统服务引入生态风险评价中进行发展和完善,成为了当前生态风险评价研究的前沿和热点。系统分析了生态系统服务在生态风险评价中的应用,指出生态系统服务在问题形成阶段中可明确保护对象和属性,在风险分析阶段可联系生态系统结构过程作用,在风险表征阶段及后续阶段能可提供清晰明确的评价结果,加强风险交流和管理,能有效地改进生态系统传统生态风险评价。在实践上,基于生态系统服务的生态风险评价可从3个不同层面开展:一是针对外界压力对某类特定功能或者系统中某些服务功能的影响,构建基于某种特定服务的实体属性评价方法;二是针对外界压力作用下生态系统结构与过程变化下对功能影响,构建基于复杂生态系统作用的评价方法,实现对生态风险的模拟评价;三是评价社会生态系统下外界驱动对人类福祉的影响时,可将DPSIR(Drive-Pressure-State-Impact-Response)理论模型运用到生态风险管理中,也可基于景观生态系统服务与压力源的空间作用关系,实现社会生态系统风险评价与管理。作为生态风险表征手段,可基于生态系统服务损失与不利服务进行表征,也可选取热力学等指标作为评估量纲。从理论、评价方法、风险管理等方面对基于生态系统服务生态风险评价给予展望。  相似文献   

16.
Establishing reference conditions for European streams   总被引:2,自引:0,他引:2  
Nijboer  R.C.  Johnson  R.K.  Verdonschot  P.F.M.  Sommerhäuser  M.  Buffagni  A. 《Hydrobiologia》2004,516(1-3):91-105
The European Water Framework Directive stipulates that Member States have to assess the ecological status of a water body by comparing the present to the expected reference condition. In the AQEM project participating countries used the criteria from the Water Framework Directive to select reference sites for each stream type. The purpose of this study was to evaluate the suitability of these criteria and to validate the reference conditions chosen, by comparing the classification of sites before analysis with the final assessment of the sites using the assessment system which was developed within the AQEM project. Our study showed that not all criteria for reference conditions could be met for all stream types. This implies that `true' reference sites could not be selected for all stream types within the AQEM project. In our study, the differences between ecoregions, countries, and stream types were interpreted in terms of human impact. Validation of reference conditions showed differences between classification of sites as reference sites based on criteria to be used in the field and directly interpreting environmental or biological data and the result of the final assessment system. In some countries it was not possible to select reference conditions, because most of the a priori criteria were met. For example, reference conditions for Dutch stream types were established using historical data and predictions based on data from other geographical regions. Using data from adjacent countries appeared to be a feasible method for establishing reference conditions. Reference sites taken from other geographical areas represented a higher ecological quality than the Dutch sites of good ecological quality. However, metric results showed a large overlap between good and high ecological status. Historical information, on the other hand, was not found to be useful in metric calculations because of the confounding differences in sampling methods. One strong advantage of using historical information is that rare species that are locally extinct but still occur in the same stream type in other geographical areas can be added to the expected reference conditions. When and which methods can be used for establishing reference conditions is illustrated in a decision tree.  相似文献   

17.
Genetic biocontrol of invasive aquatic species proposes to introduce, for control purposes, a genetically modified (GM) version of an invasive fish species to a targeted aquatic environment. Safe deployment and long term use of such technologies will depend on identifying and managing possible unintended effects to the natural environment. Environmental risk analysis (ERA) is a method for identifying the likelihood and consequences of unintended impacts, and for developing risk management strategies. For the unique situation of genetically modified biocontrol organisms (GMBOs), we review the latest thinking in ERA methodologies for GM fish and explore how terminology and assumptions from ERAs of traditional, non-modified biocontrol organisms and GM fish will need to be recast in ERAs of GMBOs. We also outline some special considerations that an ERA of a GMBOs will have to contend with: non-intuitive potential hazards; uncertainty introduced by extrapolating from domestic systems to natural ecosystems; redundancy in risk management options; and challenges of stakeholder engagement related to new technologies.  相似文献   

18.
流域生态风险评价研究进展   总被引:19,自引:8,他引:19  
流域生态风险评价是流域生态环境保护与管理的重要研究内容,与一般的区域生态风险评价相比,具有其独特的流域特征。在已有研究基础上,对流域生态风险评价进行了概念界定与特征分析,并按照风险源、生态受体、生态终点的分类标准对流域生态风险评价进行了类型划分,简要评述了流域生态风险评价的相关研究主题,并尝试构建反映流域时空尺度变化规律的生态风险评价概念模型。最后针对流域生态风险评价的研究现状,重点讨论了目前存在的不足及未来的研究趋向。  相似文献   

19.
The need for the integration of the assessment of human and ecological risks in contaminated areas, such as derelict mines, widely increases. The risk assessment process is becoming a powerful tool to provide sound scientific bases for decision-making processes. In Portugal, the risk assessment process is in its early years and the lack of multidisciplinary teams of experts is frequently mentioned as the main obstacle to its implementation. Therefore, the majority of the reclamation actions are based on impact assessment studies that usually are characterized by few biological and toxicological considerations. In order to account for some of these constraints, the ecological risk assessment framework proposed by the U.S. Environmental Protection Agency was used to plan the assessment of human and ecological risks posed by the high concentrations of metals scattered in the vicinity of S. Domingos mine, a cuprous pyrite mine located in the Southeast Alentejo (Portugal). This study presents the problem formulation phase of the assessment. It includes all the scientific information available for the area, a conceptual model, and an analysis plan for the risk assessment process. Following a tiered approach, several tasks were planned in order to acquire chemical, toxicological, and ecological information, in order to compensate for the lack of toxicity data for site-specific species.  相似文献   

20.
露天煤矿区生态风险评价方法   总被引:26,自引:5,他引:26  
程建龙  陆兆华  范英宏 《生态学报》2004,24(12):2945-2950
以露天煤矿区这一脆弱生态系统为对象进行了生态风险评价方法的探讨 ,阐述了生态风险评价的基本概念。针对露天矿区生态环境特点 ,通过描述露天矿区的主要生态环境问题 ,分析了矿区风险源、风险受体以及评价终点 ,最后建立了典型露天煤矿区生态风险的评价指标体系 ,对露天矿区这一典型退化生态系统进行了生态风险评价方法及评价步骤的探索  相似文献   

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